Synthesis, Rheological Characterization, and Tribological Performance of Olive Biolubricant Enhanced with MoS2 Additive

The stringent environmental regulations, non-renewability, poor biodegradability, and toxic nature of petroleum oil motivate researchers to seek eco-friendly biodegradable alternatives synthesized from vegetable oil feedstock. In Industry, biolubricants synthesized from vegetable oil are gaining more importance because of their renewable, eco-friendly, and less toxic nature and excellent lubrication properties such as high viscosity index, high flash point, high lubricity, and low volatility. In this study, olive biolubricant was synthesized using the transesterification method, and molybdenum disulfide (MoS2) additive was blended in olive biolubricant with 1 wt.%, 2 wt.%, and 3 wt.% concentration. The FTIR technique was used to identify the synthesized biolubricant. The effect of olive biolubricant enhanced with MoS2 on the tribological performance of journal bearing has been measured using a pin-on-disc tribometer under a boundary and thin film lubrication regime and compared with synthetic lubricant SAE20W40. The surface of the pin after the wear test was analyzed using an optical microscope. The rheological, physicochemical, and thermal properties of olive biolubricant with MoS2 were found to be reasonable compared to SAE20W40 lubricant. Test results reveal that olive biolubricant with MoS2 has excellent rheological and tribological properties compared to synthetic lubricant. Olive biolubricant blended with 3 wt.% MoS2 could be considered a better sustainable biolubricant which would help to reduce the global demand for petroleum and synthetic-based lubricants.